kind of confused here, are they the same or API is better and medical or can I keep using the prime, my betta has been folding his fins in and I think is due to stress and not eating... he is better now I gave in on the blood worms and started feeding those trying to sneak the pellets in with it but he is quite selective even with those.. LOL... but still the fin folding has increased... will do 50% water change and I want to know if to get the API or just prime and salt would do, I have a 10 gal. tank and 9 neon tetras and a beta, they are great together no signs of aggression in almost 2 weeks they've been together.. thank you for the help and aclaration.